The invention relates to a case for glasses, consisting of a larger half-shell and a smaller half-shell made both of stiff material as metal or plastic and linked together by a hinge in such a way as to allow the smaller half-shell to progressively insert into the larger half-shell when the case is in closed position, assuming a plurality of progressive deeper insertion positions, with snap-locking means provided at the front side of the case opposite to the hinge and consisting of a plurality of equally spaced projections or cavities which extend on the inner side of the-front wall of the larger half-shell parallelly to the free edge of this wall and correspond to the progressive insertion positions, and of a cog means which project outwardly on the free edge of the front wall of the smaller half-shell and co-operate with the projections or cavities as to snap-locking the two half-shells together in each of the progressive insertion positions, according to the pre-characterising part of claim 1.
A case of this kind but suitable for prepared foodstuff is known from the document GB 2 255 767. The cog means provided on the smaller half-shell of this known case and co-operating with the equally spaced projections or cavities of the larger half-shell are formed of a plurality of cogs or corrugations which extend to a great part of the perimeter of the case and particularly to the whole length of the front wall of the case. Therefore in each position (with the exception of the first) of the plurality of progressive deeper insertion positions, more than one cog of the smaller half-shell is engaged in the projections or cavities of the larger half-shell.
According to the characterising part of the claim 1, the present invention consists in the combination of the following features:
a) the cog means of the smaller half-shell comprise only one single cog,
b) the single cog and the projections or cavities have a length shorter than the length of the corresponding front walls of the half-shells and are provided in coincident median strips of these walls,
c) the cog-bearing front wall of the smaller half-shell has such an elastic deformability as to allow to be pushed inwardly for disengaging the cog from the projections or cavities,
d) in a substantially central position in the outer side of the bottom wall of the smaller half-shell a grasping recess is provided which is dimensioned in such a way as to allow a finger of the hand to be at least partially housed therein,
e) on the outer side of the front wall of the smaller half-shell outside the larger half-shell when the smaller half-shell is in the completely inserted position, a grasping extension is provided which projects beyond the front wall of the larger half-shell and allows to push inwardly the front wall of the smaller half shell also in its completely inserted position.
Further improvements of the invention form the subject of the dependent claims.